In anesthesia and respiratory care breathing systems, it has been found that it is desirable at times to filter gases or fluids prior to their introduction to the patient. An example of a system of this type is disclosed in U.S. Pat. No. 3,556,097.
On occasion, certain problems occur during the filtering process which require independent consideration. For example in handling certain types of gases an electrical problem occurs which makes it desirable to have a filter which is of a conductive material to alleviate the problems. However, with known conductive materials within a reasonable cost range, there is no known material which is transparent in nature. This combination leads to an additional concern. During the handling of the gases, particularly gases which have been passed through absorbers and vaporizers, during the filtering process a certain amount of condensation occurs as the gas passes through the filter medium. The condensation on a continuous basis results in a condensate build-up which eventually would clog the filter. With conductive housings of a non-transparent nature it is impossible to observe the condensate build-up within the filter and, consequently, with known systems it is necessary to replace the filter at periodic intervals as a safety measure without actually knowing the extent of condensate build-up.
Carrying this concern one step further, with the filters presently in use there is no structure which provides for removal of condensate build-up were it possible to observe this development. The filters could be used until they completely fill beyond an acceptable condensate level and then they would have to be removed from the system.
Another consideration of the known filters for the environment under consideration is that they are generally designed to interconnect with a system of a predetermined arrangement. It would be extremely advantageous to provide a filter which is adaptable for connection with a variety of different types of breathing systems without altering the physical structure of the filter itself.
Finally, above all, it is imperative that the filter be of low cost disposable materials so as to be compatible with general systems presently in use which are primarily designed for single use. On the other hand, the filter should be versatile enough so that the condensate build-up can be removed during the single use without the necessity of having to use a multiple of filters for an individual patient.